diff --git a/bin/delv/delv.c b/bin/delv/delv.c
index 7155d4b299..144b26c1f0 100644
--- a/bin/delv/delv.c
+++ b/bin/delv/delv.c
@@ -635,14 +635,12 @@ key_fromconfig(const cfg_obj_t *key, dns_client_t *client) {
 	if (!match_root) {
 		return (ISC_R_SUCCESS);
 	}
-	if (!root_validation && match_root) {
+
+	if (!root_validation) {
 		return (ISC_R_SUCCESS);
 	}
 
-	if (match_root) {
-		delv_log(ISC_LOG_DEBUG(3), "adding trust anchor %s",
-			  trust_anchor);
-	}
+	delv_log(ISC_LOG_DEBUG(3), "adding trust anchor %s", trust_anchor);
 
 	flags = cfg_obj_asuint32(cfg_tuple_get(key, "flags"));
 	proto = cfg_obj_asuint32(cfg_tuple_get(key, "protocol"));
diff --git a/bin/dig/dighost.c b/bin/dig/dighost.c
index 222b7875bf..5e24af65e5 100644
--- a/bin/dig/dighost.c
+++ b/bin/dig/dighost.c
@@ -649,7 +649,6 @@ make_empty_lookup(void) {
 	looknew->use_usec = false;
 	looknew->nocrypto = false;
 	looknew->ttlunits = false;
-	looknew->ttlunits = false;
 	looknew->expandaaaa = false;
 	looknew->qr = false;
 	looknew->accept_reply_unexpected_src = false;
diff --git a/bin/dnssec/dnssec-signzone.c b/bin/dnssec/dnssec-signzone.c
index 5f3cfa9ad4..8f3e74cb2c 100644
--- a/bin/dnssec/dnssec-signzone.c
+++ b/bin/dnssec/dnssec-signzone.c
@@ -1706,7 +1706,6 @@ remove_records(dns_dbnode_t *node, dns_rdatatype_t which,
 			result = dns_db_deleterdataset(gdb, node, gversion,
 						       type, covers);
 			check_result(result, "dns_db_deleterdataset()");
-			continue;
 		}
 	}
 	dns_rdatasetiter_destroy(&rdsiter);
@@ -3583,7 +3582,6 @@ main(int argc, char *argv[]) {
 			outputformat = dns_masterformat_raw;
 		} else if (strncasecmp(outputformatstr, "raw=", 4) == 0) {
 			char *end;
-			outputformat = dns_masterformat_raw;
 
 			outputformat = dns_masterformat_raw;
 			rawversion = strtol(outputformatstr + 4, &end, 10);
diff --git a/bin/named/fuzz.c b/bin/named/fuzz.c
index 02c75d303a..0064d92075 100644
--- a/bin/named/fuzz.c
+++ b/bin/named/fuzz.c
@@ -142,7 +142,7 @@ fuzz_thread_client(void *arg) {
 		 * Read the reply message from named to unclog it. Don't
 		 * bother if there isn't a reply.
 		 */
-		recvfrom(sockfd, buf, 65536, MSG_DONTWAIT, NULL, NULL);
+		(void)recvfrom(sockfd, buf, 65536, MSG_DONTWAIT, NULL, NULL);
 
 		while (!ready)
 			pthread_cond_wait(&cond, &mutex);
@@ -412,8 +412,8 @@ fuzz_thread_resolver(void *arg) {
 		 * Flush any pending data on the authoritative server.
 		 */
 		socklen = sizeof(recvaddr);
-		sent = recvfrom(listenfd, rbuf, 65536, MSG_DONTWAIT,
-			(struct sockaddr *) &recvaddr, &socklen);
+		(void)recvfrom(listenfd, rbuf, 65536, MSG_DONTWAIT,
+			       (struct sockaddr *) &recvaddr, &socklen);
 
 		/*
 		 * Send a fixed client query to named(resolver) of
@@ -511,7 +511,8 @@ fuzz_thread_resolver(void *arg) {
 				 * to the client(query driver), so we're
 				 * done.
 				 */
-				recvfrom(sockfd, buf, 65536, 0, NULL, NULL);
+				(void)recvfrom(sockfd, buf, 65536, 0, NULL,
+					       NULL);
 				break;
 			}
 
diff --git a/contrib/dlz/drivers/dlz_bdbhpt_driver.c b/contrib/dlz/drivers/dlz_bdbhpt_driver.c
index 1f20015860..4d3d935607 100644
--- a/contrib/dlz/drivers/dlz_bdbhpt_driver.c
+++ b/contrib/dlz/drivers/dlz_bdbhpt_driver.c
@@ -591,8 +591,7 @@ bdbhpt_lookup(const char *zone, const char *name, void *driverarg,
 	if (data_cursor != NULL)
 		data_cursor->c_close(data_cursor);
 
-	if (keyStr != NULL)
-		free(keyStr);
+	free(keyStr);
 	if (tmp != NULL)
 		free(tmp);
 
diff --git a/contrib/dlz/drivers/dlz_mysql_driver.c b/contrib/dlz/drivers/dlz_mysql_driver.c
index da1c9393c0..5e4366dac5 100644
--- a/contrib/dlz/drivers/dlz_mysql_driver.c
+++ b/contrib/dlz/drivers/dlz_mysql_driver.c
@@ -138,8 +138,7 @@ mysql_get_resultset(const char *zone, const char *record,
 
 	/* if DBI is null, can't do anything else */
 	if (dbi == NULL) {
-		result = ISC_R_FAILURE;
-		goto cleanup;
+		return (ISC_R_FAILURE);
 	}
 
 	/* what type of query are we going to run? */
@@ -330,10 +329,6 @@ mysql_get_resultset(const char *zone, const char *record,
  cleanup:
 	/* it's always good to cleanup after yourself */
 
-	/* if we couldn't even get DBI, just return NULL */
-	if (dbi == NULL)
-		return ISC_R_FAILURE;
-
 	/* free dbi->zone string */
 	if (dbi->zone != NULL)
 		isc_mem_free(named_g_mctx, dbi->zone);
diff --git a/contrib/dlz/drivers/dlz_odbc_driver.c b/contrib/dlz/drivers/dlz_odbc_driver.c
index c5a1a156f3..59e31441e0 100644
--- a/contrib/dlz/drivers/dlz_odbc_driver.c
+++ b/contrib/dlz/drivers/dlz_odbc_driver.c
@@ -35,7 +35,7 @@
 
 /*
  * Copyright (C) 1999-2001, 2016  Internet Systems Consortium, Inc. ("ISC")
- * 
+ *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
@@ -433,8 +433,7 @@ odbc_get_resultset(const char *zone, const char *record,
 
 	/* if DBI is null, can't do anything else */
 	if (dbi == NULL) {
-		result = ISC_R_FAILURE;
-		goto cleanup;
+		return (ISC_R_FAILURE);
 	}
 
 	/* what type of query are we going to run? */
@@ -616,10 +615,6 @@ odbc_get_resultset(const char *zone, const char *record,
 
  cleanup:	/* it's always good to cleanup after yourself */
 
-		/* if we couldn't even allocate DBI, just return NULL */
-	if (dbi == NULL)
-		return ISC_R_FAILURE;
-
 	/* free dbi->zone string */
 	if (dbi->zone != NULL)
 		isc_mem_free(named_g_mctx, dbi->zone);
diff --git a/contrib/dlz/drivers/dlz_postgres_driver.c b/contrib/dlz/drivers/dlz_postgres_driver.c
index 3bd72b59ee..ec6fd93686 100644
--- a/contrib/dlz/drivers/dlz_postgres_driver.c
+++ b/contrib/dlz/drivers/dlz_postgres_driver.c
@@ -303,8 +303,7 @@ postgres_get_resultset(const char *zone, const char *record,
 
 	/* if DBI is null, can't do anything else */
 	if (dbi == NULL) {
-		result = ISC_R_FAILURE;
-		goto cleanup;
+		return (ISC_R_FAILURE);
 	}
 
 	/* what type of query are we going to run? */
@@ -564,10 +563,6 @@ postgres_get_resultset(const char *zone, const char *record,
 		      "%d cleaning up", dlz_thread_num);
 #endif
 
-	/* if we couldn't even allocate DBI, just return NULL */
-	if (dbi == NULL)
-		return ISC_R_FAILURE;
-
 	/* free dbi->zone string */
 	if (dbi->zone != NULL)
 		isc_mem_free(named_g_mctx, dbi->zone);
diff --git a/contrib/dlz/modules/bdbhpt/dlz_bdbhpt_dynamic.c b/contrib/dlz/modules/bdbhpt/dlz_bdbhpt_dynamic.c
index 43e54f9792..859605f63c 100644
--- a/contrib/dlz/modules/bdbhpt/dlz_bdbhpt_dynamic.c
+++ b/contrib/dlz/modules/bdbhpt/dlz_bdbhpt_dynamic.c
@@ -594,8 +594,7 @@ isc_result_t dlz_lookup(const char *zone, const char *name, void *dbdata,
 	if (data_cursor != NULL)
 		data_cursor->c_close(data_cursor);
 	
-	if (keyStr != NULL)
-		free(keyStr);
+	free(keyStr);
 	if (tmp != NULL)
 		free(tmp);
 	
diff --git a/contrib/dlz/modules/common/dlz_dbi.c b/contrib/dlz/modules/common/dlz_dbi.c
index 7b4c9da5f0..e4c27bb746 100644
--- a/contrib/dlz/modules/common/dlz_dbi.c
+++ b/contrib/dlz/modules/common/dlz_dbi.c
@@ -255,8 +255,7 @@ build_querylist(const char *query_str, char **zone, char **record,
 
  flag_fail:
 	/* get rid of what was build of the query list */
-	if (tql != NULL)
-		destroy_querylist(&tql);
+	destroy_querylist(&tql);
 	return (result);
 }
 
diff --git a/contrib/dlz/modules/filesystem/dlz_filesystem_dynamic.c b/contrib/dlz/modules/filesystem/dlz_filesystem_dynamic.c
index 494bd1805a..a143fd5e96 100644
--- a/contrib/dlz/modules/filesystem/dlz_filesystem_dynamic.c
+++ b/contrib/dlz/modules/filesystem/dlz_filesystem_dynamic.c
@@ -595,7 +595,6 @@ dlz_allnodes(const char *zone, void *dbdata, dns_sdlzallnodes_t *allnodes) {
 	dir_entry_t *next_de;
 
 	basepath = NULL;
-	dir_list = NULL;
 
 	/* allocate memory for list */
 	dir_list = malloc(sizeof(dlist_t));
diff --git a/contrib/dlz/modules/mysql/dlz_mysql_dynamic.c b/contrib/dlz/modules/mysql/dlz_mysql_dynamic.c
index a325fc5d22..84ab45f6e0 100644
--- a/contrib/dlz/modules/mysql/dlz_mysql_dynamic.c
+++ b/contrib/dlz/modules/mysql/dlz_mysql_dynamic.c
@@ -246,8 +246,7 @@ mysql_get_resultset(const char *zone, const char *record,
 #endif /* PTHREADS */
 
 	if (dbi == NULL) {
-		result = ISC_R_FAILURE;
-		goto cleanup;
+		return (ISC_R_FAILURE);
 	}
 
 	/* what type of query are we going to run? */
@@ -401,9 +400,6 @@ mysql_get_resultset(const char *zone, const char *record,
 		result = ISC_R_FAILURE;
 
  cleanup:
-	if (dbi == NULL)
-		return (ISC_R_FAILURE);
-
 	if (dbi->zone != NULL) {
 		free(dbi->zone);
 		dbi->zone = NULL;
diff --git a/contrib/dlz/modules/sqlite3/dlz_sqlite3_dynamic.c b/contrib/dlz/modules/sqlite3/dlz_sqlite3_dynamic.c
index 2d7d0b0675..caf519f5d5 100644
--- a/contrib/dlz/modules/sqlite3/dlz_sqlite3_dynamic.c
+++ b/contrib/dlz/modules/sqlite3/dlz_sqlite3_dynamic.c
@@ -35,7 +35,7 @@
 
 /*
  * Copyright (C) 1999-2001, 2013-2014, 2016  Internet Systems Consortium, Inc. ("ISC")
- * 
+ *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
@@ -277,8 +277,7 @@ sqlite3_get_resultset(const char *zone, const char *record,
 #endif /* PTHREADS */
 
 	if (dbi == NULL) {
-		result = ISC_R_FAILURE;
-		goto cleanup;
+		return (ISC_R_FAILURE);
 	}
 
 	/* what type of query are we going to run? */
@@ -431,16 +430,13 @@ sqlite3_get_resultset(const char *zone, const char *record,
 	result = ISC_R_SUCCESS;
 	if (query == COUNTZONE) {
 		sqlite3_free_table(rs->pazResult);
-		if (rs == NULL)
-			result = ISC_R_FAILURE;
 	}
 
-	*rsp = rs;
+	if (rsp != NULL) {
+		*rsp = rs;
+	}
 
  cleanup:
-	if (dbi == NULL)
-		return (ISC_R_FAILURE);
-
 	if (dbi->zone != NULL) {
 		free(dbi->zone);
 		dbi->zone = NULL;
diff --git a/lib/dns/dnsrps.c b/lib/dns/dnsrps.c
index 7ecc53f1c0..c4f68e15b3 100644
--- a/lib/dns/dnsrps.c
+++ b/lib/dns/dnsrps.c
@@ -146,7 +146,7 @@ dns_dnsrps_server_create(void) {
 
 	isc_mutex_init(&dnsrps_mutex);
 
-	librpz->set_log(&dnsrps_log_fnc, NULL);
+	librpz->set_log(dnsrps_log_fnc, NULL);
 
 	clist = librpz->clist_create(&emsg, dnsrps_lock, dnsrps_unlock,
 				     dnsrps_mutex_destroy, &dnsrps_mutex,
diff --git a/lib/dns/dnstap.c b/lib/dns/dnstap.c
index 7a4a01ea60..4e7d8e7b48 100644
--- a/lib/dns/dnstap.c
+++ b/lib/dns/dnstap.c
@@ -266,14 +266,17 @@ dns_dt_create(isc_mem_t *mctx, dns_dtmode_t mode, const char *path,
 	*envp = env;
 
  cleanup:
-	if (ffwopt != NULL)
+	if (ffwopt != NULL) {
 		fstrm_file_options_destroy(&ffwopt);
+	}
 
-	if (fuwopt != NULL)
+	if (fuwopt != NULL) {
 		fstrm_unix_writer_options_destroy(&fuwopt);
+	}
 
-	if (fwopt != NULL)
+	if (fwopt != NULL) {
 		fstrm_writer_options_destroy(&fwopt);
+	}
 
 	if (result != ISC_R_SUCCESS) {
 		isc_mutex_destroy(&env->reopen_lock);
@@ -337,8 +340,7 @@ dns_dt_reopen(dns_dtenv_t *env, int roll) {
 	 */
 	fwopt = fstrm_writer_options_init();
 	if (fwopt == NULL) {
-		isc_task_endexclusive(env->reopen_task);
-		return (ISC_R_NOMEMORY);
+		CHECK(ISC_R_NOMEMORY);
 	}
 
 	res = fstrm_writer_options_add_content_type(fwopt,
@@ -414,17 +416,21 @@ dns_dt_reopen(dns_dtenv_t *env, int roll) {
 	}
 
  cleanup:
-	if (ffwopt != NULL)
-		fstrm_file_options_destroy(&ffwopt);
-
-	if (fw != NULL)
+	if (fw != NULL) {
 		fstrm_writer_destroy(&fw);
+	}
 
-	if (fwopt != NULL)
-		fstrm_writer_options_destroy(&fwopt);
-
-	if (fuwopt != NULL)
+	if (fuwopt != NULL) {
 		fstrm_unix_writer_options_destroy(&fuwopt);
+	}
+
+	if (ffwopt != NULL) {
+		fstrm_file_options_destroy(&ffwopt);
+	}
+
+	if (fwopt != NULL) {
+		fstrm_writer_options_destroy(&fwopt);
+	}
 
 	isc_task_endexclusive(env->reopen_task);
 
diff --git a/lib/dns/ds.c b/lib/dns/ds.c
index 857afe7ef2..8958fb89cf 100644
--- a/lib/dns/ds.c
+++ b/lib/dns/ds.c
@@ -118,8 +118,6 @@ dns_ds_buildrdata(dns_name_t *owner, dns_rdata_t *key,
 	ret = dns_rdata_fromstruct(rdata, key->rdclass, dns_rdatatype_ds,
 				   &ds, &b);
 end:
-	if (md != NULL) {
-		isc_md_free(md);
-	}
+	isc_md_free(md);
 	return (ret);
 }
diff --git a/lib/dns/openssldh_link.c b/lib/dns/openssldh_link.c
index 7f9c244c6a..ff14c7e956 100644
--- a/lib/dns/openssldh_link.c
+++ b/lib/dns/openssldh_link.c
@@ -306,7 +306,7 @@ openssldh_generate(dst_key_t *key, int generator, void (*callback)(int)) {
 		} else {
 			/* cppcheck-suppress unreadVariable */
 			u.fptr = callback;
-			BN_GENCB_set(cb, &progress_cb, u.dptr);
+			BN_GENCB_set(cb, progress_cb, u.dptr);
 		}
 
 		if (!DH_generate_parameters_ex(dh, key->key_size, generator,
diff --git a/lib/dns/opensslecdsa_link.c b/lib/dns/opensslecdsa_link.c
index 895f16da45..04cef6dbda 100644
--- a/lib/dns/opensslecdsa_link.c
+++ b/lib/dns/opensslecdsa_link.c
@@ -186,8 +186,7 @@ opensslecdsa_sign(dst_context_t *dctx, isc_buffer_t *sig) {
 	ret = ISC_R_SUCCESS;
 
  err:
-	if (eckey != NULL)
-		EC_KEY_free(eckey);
+	EC_KEY_free(eckey);
 	return (ret);
 }
 
@@ -251,8 +250,7 @@ opensslecdsa_verify(dst_context_t *dctx, const isc_region_t *sig) {
  err:
 	if (ecdsasig != NULL)
 		ECDSA_SIG_free(ecdsasig);
-	if (eckey != NULL)
-		EC_KEY_free(eckey);
+	EC_KEY_free(eckey);
 	return (ret);
 }
 
@@ -340,8 +338,7 @@ opensslecdsa_generate(dst_key_t *key, int unused, void (*callback)(int)) {
 	ret = ISC_R_SUCCESS;
 
  err:
-	if (eckey != NULL)
-		EC_KEY_free(eckey);
+	EC_KEY_free(eckey);
 	return (ret);
 }
 
@@ -396,8 +393,7 @@ opensslecdsa_todns(const dst_key_t *key, isc_buffer_t *data) {
 	ret = ISC_R_SUCCESS;
 
  err:
-	if (eckey != NULL)
-		EC_KEY_free(eckey);
+	EC_KEY_free(eckey);
 	return (ret);
 }
 
@@ -497,8 +493,7 @@ opensslecdsa_tofile(const dst_key_t *key, const char *directory) {
 	ret = dst__privstruct_writefile(key, &priv, directory);
 
  err:
-	if (eckey != NULL)
-		EC_KEY_free(eckey);
+	EC_KEY_free(eckey);
 	if (buf != NULL)
 		isc_mem_put(key->mctx, buf, BN_num_bytes(privkey));
 	return (ret);
@@ -529,8 +524,7 @@ ecdsa_check(EC_KEY *eckey, dst_key_t *pub)
 		DST_RET (ISC_R_SUCCESS);
 
  err:
-	if (pubeckey != NULL)
-		EC_KEY_free(pubeckey);
+	EC_KEY_free(pubeckey);
 	return (ret);
 }
 
diff --git a/lib/dns/openssleddsa_link.c b/lib/dns/openssleddsa_link.c
index 8357bee058..717e9eaa82 100644
--- a/lib/dns/openssleddsa_link.c
+++ b/lib/dns/openssleddsa_link.c
@@ -367,8 +367,7 @@ openssleddsa_sign(dst_context_t *dctx, isc_buffer_t *sig) {
 	ret = ISC_R_SUCCESS;
 
  err:
-	if (ctx != NULL)
-		EVP_MD_CTX_free(ctx);
+	EVP_MD_CTX_free(ctx);
 	isc_buffer_free(&buf);
 	dctx->ctxdata.generic = NULL;
 
@@ -435,8 +434,7 @@ openssleddsa_verify(dst_context_t *dctx, const isc_region_t *sig) {
 	}
 
  err:
-	if (ctx != NULL)
-		EVP_MD_CTX_free(ctx);
+	EVP_MD_CTX_free(ctx);
 	isc_buffer_free(&buf);
 	dctx->ctxdata.generic = NULL;
 
@@ -507,8 +505,7 @@ openssleddsa_generate(dst_key_t *key, int unused, void (*callback)(int)) {
 	ret = ISC_R_SUCCESS;
 
  err:
-	if (ctx != NULL)
-		EVP_PKEY_CTX_free(ctx);
+	EVP_PKEY_CTX_free(ctx);
 	return (ret);
 }
 
diff --git a/lib/dns/opensslrsa_link.c b/lib/dns/opensslrsa_link.c
index ecf13c7625..1a61c9f366 100644
--- a/lib/dns/opensslrsa_link.c
+++ b/lib/dns/opensslrsa_link.c
@@ -497,7 +497,7 @@ opensslrsa_generate(dst_key_t *key, int exp, void (*callback)(int)) {
 	} else {
 		/* cppcheck-suppress unreadVariable */
 		u.fptr = callback;
-		BN_GENCB_set(cb, &progress_cb, u.dptr);
+		BN_GENCB_set(cb, progress_cb, u.dptr);
 	}
 
 	if (RSA_generate_key_ex(rsa, key->key_size, e, cb)) {
@@ -600,8 +600,7 @@ opensslrsa_todns(const dst_key_t *key, isc_buffer_t *data) {
 
 	ret = ISC_R_SUCCESS;
  err:
-	if (rsa != NULL)
-		RSA_free(rsa);
+	RSA_free(rsa);
 	return (ret);
 }
 
diff --git a/lib/isc/xoshiro128starstar.c b/lib/isc/xoshiro128starstar.c
index 0882041a74..abf1ea8455 100644
--- a/lib/isc/xoshiro128starstar.c
+++ b/lib/isc/xoshiro128starstar.c
@@ -50,7 +50,7 @@ static __declspec( thread ) uint32_t seed[4];
 #else
 #if defined(_WIN32) || defined(_WIN64)
 #include <windows.h>
-static volatile HANDLE _mutex = NULL;
+static volatile void *_mutex = NULL;
 
 /*
  * Initialize the mutex on the first lock attempt. On collision, each thread
@@ -60,7 +60,7 @@ static volatile HANDLE _mutex = NULL;
 #define _LOCK() \
 	do {								\
 		if (!_mutex) {						\
-			HANDLE p = CreateMutex(NULL, FALSE, NULL);	\
+			void *p = CreateMutex(NULL, FALSE, NULL);	\
 			if (InterlockedCompareExchangePointer		\
 			    ((void **)&_mutex, (void *)p, NULL)) {	\
 				CloseHandle(p);				\
diff --git a/lib/isccfg/namedconf.c b/lib/isccfg/namedconf.c
index b6c70e4bc6..d427ec488d 100644
--- a/lib/isccfg/namedconf.c
+++ b/lib/isccfg/namedconf.c
@@ -312,7 +312,7 @@ static cfg_type_t cfg_type_matchtype = {
 
 static cfg_type_t cfg_type_matchname = {
 	"optional_matchname", parse_matchname, cfg_print_ustring,
-	&doc_matchname, &cfg_rep_tuple, &cfg_type_ustring
+	doc_matchname, &cfg_rep_tuple, &cfg_type_ustring
 };
 
 /*%
diff --git a/lib/ns/hooks.c b/lib/ns/hooks.c
index d89a063ad2..8a60042c51 100644
--- a/lib/ns/hooks.c
+++ b/lib/ns/hooks.c
@@ -211,9 +211,7 @@ cleanup:
 					     sizeof(*plugin));
 		}
 
-		if (handle != NULL) {
-			(void) dlclose(handle);
-		}
+		(void) dlclose(handle);
 	}
 
 	return (result);
diff --git a/lib/ns/xfrout.c b/lib/ns/xfrout.c
index 55609bbbaa..7672f59d9a 100644
--- a/lib/ns/xfrout.c
+++ b/lib/ns/xfrout.c
@@ -279,7 +279,7 @@ ixfr_rrstream_current(rrstream_t *rs,
 static void
 ixfr_rrstream_destroy(rrstream_t **rsp) {
 	ixfr_rrstream_t *s = (ixfr_rrstream_t *) *rsp;
-	if (s->journal != 0)
+	if (s->journal != NULL)
 		dns_journal_destroy(&s->journal);
 	isc_mem_putanddetach(&s->common.mctx, s, sizeof(*s));
 }